To vegetarians/vegans....?

Yeah, when I'm not "milked" for a period of time (usually 8-12 hours) I get cranky and am in pain, but it subsides after another 12 hours. The poor thing would be better off not being constantly milked. I use to pump when I went back to work, it hurts!!! Why should a cow have to go through that agianst its will. Even animals that wean their young, control the situation...but as soon as we humans get in the picture, that cow has to continue past its breaking point! There's also a bunch of other reasons, but this is from a feeding point of view and I'm sure many other people will chime in about how they "aren't hurt", or however you said it!